Method of and apparatus for drying air.



H. G. GARDNER. METHOD OF AND APPARATUS FOR DRYING AIR. APPLICATION FILEDNOV. 17, 1904.

910,525. h Patented Jan. 26, 1909.

3 SHEETS-SHEET 1.

H. G. GARDNER. METHOD OF AND APPARATUS FOR DRYING AIR.

APPLICATION PIL ED NOV. 17,1904.

Patented Jan. 26, 1909.

3 SHEETSSHEBT 2.

W/aZreappes:

H. G. GARDNER. METHOD OF AND APPARATUS FOR DRYING AIR.

APPLICATION FILED NOV. 17, 1904.

Patented Jan. 26, 1909.

3 SHEETS-SHEET 3 HORACE C. GARDNER, 0F OHIOAGQ, ILLINOIS.

I METHQD OF AND APPARATUS FOR DRYING ,AIR.

Specification of Letters Patent.

Patented Jan. 26, 1909.

Application filed November 17 1904. Serial No. 233,196.

To all whom it may concern:

Be it known that I, Holmes 0. GARDNER, a citizen of the United States,residing. at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Method of and Apparatus for DryingAir, of which the following is a specification, reference being had tothe accompanying drawings.

My invention relates to a new and improved method of and apparatus fordrying air for use in blast furnaces and other purposes.

It is well known that air thoroughly dried is more efiicient in blastfurnaces than air in which moisture is allowed to remain, and I havediscovered that bysimultaneously refrigerating the air and subjecting itto the action of a hygroscopic agent the air may be efiiciently dried;and, broadly stated, this is the gist of my invention. In carrying outthis invention 1 have also found that if the air is first cooledforinstance, by washing it with a spray of cold liquidthe cooling of theair, if it is saturated, will deprive it of a portion of its moisture,and passing the air thus cooled along and subjecting it to the action ofa refrigerated hygroscopic agent, the process. will be facilitated. Inthe carrying out of my invention too I have found that it may beefiiciently practiced by first cooling the air, as above described, andthen passing, it into a chamber where it is brought in contact with arefrigerated liquid having hygroscopic ropertics and suitably disposedto act e iciently upon the air passing through the chamber. The liquidwhich I prefer to use for this hygroscopic agent is a brine of calciumchlorid.

For the carrying out of my method of drying air I have also inventedanew and improved apparatus, which is illustrated in the accompanyingdrawings. It is obvious,

however, that my process or method of drymg air may be carried out byother means. In the drawings, Flgure 1 1s a top or plan view, partiallyin horizontal section on line 1-1 of Fig. 2 Fig. 2 is a vertical sectionon line 22 of Fig. 1; Fig. 3 is a vertical section on line 33.of Flg. 1,or on line 33 of Fig. 2; Fig. 4 is a vertical section on line 44 offigure 2 and Fig. 5 is an enlarged detail, being an isometric view of aportion of one of the brine troughs from which the brine is distributedover the refrigerating coils. v

Referring to the drawings,6 indicates a chamber, having a flaring orpyramidalshaped front 7 and a bottom 8, which slopes from' its sidestoward the center. he chamber 6 is provided with a number of coils ofpipe 9, which are connected with one another to form a continuous seriesof coils laid from one to the other in such a way that liquid passedinto the lower coil at the bottom of the right-hand end, shown in Fig.2, will pass through and out at the top coil at the left-hand end, asshown in Fig. 2. r

10 indicates a number of troughs, which are suspended from the top ofchamber 6 and extend laterally across the same the length of the coilsof pipes 9. These troughs are constructed inthe manner shown anddescribed in Letters Patent to me, No. 654,725, of date of July 31,1900. Fig. 5 shows an isometric view of a portion of one of thesetroughs.

As is shown in that figure, the troughs are V-shaped, and are composedof two side members 11-12 andtwo end members 13. The side member 1 1 issomewhat higher than the end members 13 and the other side member 12, asis best shown in Fig. 5, and is provided with openings by which it maybe boltedfor otherwise secured to the top of the chamber 6. The top andbottom edges of the side member 12 are serrated, as is shown in Fig.5,and the troughs are so disposed that the bottom edge of the serratedportion 12 lies over the pipes of the top coil, as is shown in Fig. 2and as is shown in said figure the said coils of pipe are arranged sothat the pipes of the different layers of the coil may lie substantiallyover one another.

14 indicates a pipe, which is connected with a pump 15 and is laid abovethe chamber 6, extending substantially the length thereof, as is bestshown in Fig. 2. The portion of the pipe extending over the chamber 6 isprovided with a series of outlet nozzles 16 which pierce the top of thechamber 6 and open on. the inside thereof immediately above the troughs10.

17 indicates a pipe opening from the bottom of the chamber 6 and leadingto the pump 15. l i

36 indicates'an evaporator, which may be of any well-known and approvedform, preferably a multiple-effect vacuum eva orator. As this evaporatormay be of any we -known andapprovcd construction, I have indicated itonly conventionally.

J to constantly draw from t 37 indicates a pipe leading from the eVap-.

orator 36 to the pipe 14. p

38 indicates a by-passpipe leading from the ipe 17 to the evaporator 36.

T e ump 15, when set in'motion, pumps a supp y of hygrosclppic liquid,preferably a bribe of calcium 0 orid, through the pipe 14, whence it isdischarged through the nozzles 16 into the troughs 10. When the troughs1O fill, the liquid will ass over the serrated edges upon the top oft eside member 12 and, running down the side, will be dischar ed from thepoints on the lower serrated e ges upon the tubes of the top coils 9,from which it will drip upon each pipe to the pipe below it, wetting thesurfaces of all the coils in the chamber 6. From the lowest coils itwill drop into the bottom of the chamber, from which it will be pumpedthrough the pipe 17 back into the pump 15 and thence out throughthe-tube 14, keeping up a constant circulation. Inasmuch as the moisturewill be taken out of the air in the manner hereinafter described, themoisture 'so extracted will be constantly added to the brine, whichwould weaken the solution; In order to prevent this, the bypass pipe 38is adapted e pipe'17 a suitable percentage of the brine passing throughthe pipe 17 and convey it to the evaporator 36, where it isevaporatedand concentrated; and the concentrated liquid passes through the pipe 37into pipe 14, thus preserving the norma strength 0 the solution.

18 indicates a chamber into which'air may bedriven by means of a fan 19.

20 indicates a series of coils of pipe located near the bottom of thechamber 18 and connected by a ipe 21 with the last of thecoils of pipe 9in the chamber 6. As is best shown in Fig. 1, the coils of ipe20 form acontinuous passage, and are ed out of the chamber 18 by'means of a pipe22.

23 indicates an ammonia compressor of any suitable construction. s 24indicates a pipe, which leads from the ammonia compressor 23 to acondenser 39. The condenser 39 may be of any approved and well-knownform and construction, and hence is indicated only conventionally.

40 indicates a ipe, which leads from the condenser 39 and connects withthe lowest one of the coils 9, asindicated in dotted lines of anysuitable orm and construction, 'is

opened and the liquid ammonia passes into the coils in the chamber 6.Flowing:

through all-the coils it expands into gas, and,

passing out through the pipe 21 through the coils 20 and the pipe 22, isled back-again at a low pressure into the compressor 23, where it isagain compressed and the operation repeated. The effect of causing theliquid ammonia to flow into the coils 9, and expanding on its way, topass through the pipes 21 and'coils 20 is to refrigerate to a lowtemperature the coils 9 in the chamber 6, and to cool the coils 20,which will, of course, not be cooled so much as the coils 9 as most ofthe cium chloridbrine passes from the troughs 12 over the pipes 9 itcovers the surfaces of the pipes 9 and is refrigerated to a lowtemperature.

24 indicates spray roses, which are located in the top of the chamber18, and are con- .workis done inthe chamber 6. As the cal nected bymeans of a pipe 25, as is best 26 indicates a pipe leadin out of thebottom of the chamber 18, whic is connected to the pum 42, from whichthe water is ,pum ed into t e spray roses 24. In other wor s, the waterat the bottom of the chamber 18 forms a reservoir from which the wateris pumped and kept, in circulation through the pipes 26 and 25 andthroughthe spray roses 24 into the chamber. The pipes 20, beingrefrigerated, as above described, will cool the water greatly, whereby aspray of cold water will pass from the roses 24 into the chamber 18.

27 indicates a chamber located beside the chamber 18 and separatedtherefrom by a partition 28.

29 indicates a yramidal chamber upon one side of the c amber 27 andseparated from it by a partition 30.

31 indicates a series of tubes set in the partitions 28 and ,30 andopenin at one end into the chamber 18 and at the ot. er end into thepyramidal-shaped chamber 29. The chamor 27 is connected by passages 32with the chamber 6.

33 indicates a pipe, which connects the chamber 29 with thepyramidal-shaped end 7 of the chamber 6.

34. indicates a dischar e tube opening from the top of the cham er 27,and provided-with an exhaust fan 35.

Atmos heric air is forced. by the fan 19 I into the c amber 18, where,the iumps-bein set in operation, it is sprayed y the col water issuin.from thespra roses 24'. The air in the c amber 18 is t us considerablycooled, and if it is saturated is deprived of a portion of its moisture.The spraying of the air by cold Water in the chamber 18 Will, it is 5pheric condition already be such that the air enterin the chamber isalready cold and relative y dry, the pumping the Water through the sprayroses will not be operated.

ber 18 through the tubes 31'into the pyramidal chamber 29, and thencethrough the pipe 33 intothe pyramidal head 7 of the chamber 6, whence itis forced through the chamber 6. 15

Qassingthro-ugh the chamber 6, it is brought in'contact with thehygroscopic licl luirb' such as. brine of calcium chlorid, w

, ich has been supplied to thecoils of pipe in the chamber 6 andrefrigerated to a very loW degree, as above described. Being broughtthus in contact with'the refrigerate ing hygroscopic liquid, the air isrefrigerated and the combined action of the refrigerating of the air andof the-action upon it by the brine of calcium chloridis to depriyetheair of its moisture and-to thoroughly dry it.

The air thus thoroughly dried passes through.

.the pipes 32 into the chamber 27, from Wl1enc'e it .is drawn by theexhaust fan 35 through the pipe 34 and conducted to the place at whichit is to be used.

The chamber 2 7-it will be seen operatesas a heat exchanger. The colddry air passing from the chamber 6, through and out of said chamber 27.,will cool the air passing from the chamber 18 in the pipes '31, and thuswill' render the further cooling of the air in' the chamber 6 easier. Atthe same time, the

. warmer, air passing from the chamber 18,

through the pipes 31, will raise the temper- 40 chamber -6, and thethoroughly dried' air drawn-from the chamber 27 by the fan 35 will" beraised "in temperature considerably from the chamber 6 thoroughly dried.'lhat which I claim, as m invention and deslre to secure by Lettersatent is,

1. The process of drying air, which cons'ists in passing it throughaheat exchanger, thence passing it through a chamber i1i'- gwhich the airwhile passing through the chamber is subjected to the action .ofrefrigerating means and toy the action of: a refrigerated hygroscopicagent, thence passing-the air fromsaid chamber through saidheat-exchanger, and during said process. maintaining sald hygroscopicagent at a substantially constant strength.

2. The process of drying air which con .60 sists in first cooling theair, then passing it through a heat-exchanger, thence passingit ature ofthe cold dry alr issuing from the above the temperature at which itissues agent at a substantially constant strengthf In either case, theair passes from the cham- 3. In an apparatus for drying air, thecombination with achamber, a series of pipe coils in said' chamber,means for refrigerating said pipes, means for distributing a hygroscopicsolution over said refrigerated'pipes, means for keeping saidhygroscopic solution in circulation through said chamber, and

means for maintaining said hygroscopic solu tion at a substantiallyconstant strength, of a heat-exchanger, connections between said heatexchanger and said chamber, and means for forcing air through s'aid'heatexchanger,

thence into and through said chamber,

said pipes, means for distributing a hygroscopic solution over saidrefrigerated pipes, -means for keeping said hygroscopic'solution incirculation through said chamber, and means for maintaining saidhygroscopic solution at a substantially constant strength,

of a second chamber, means for spraying cold water through saidsecondchamber, connections betweensaid first chamber and said second chamber,and means for forcing air through said second chamber thence into andthrough said first chamber, substantially as described.

drawmg a supply-of water in said second chamber therefrom and sprayingit into said second chamber, a thirdchamber, pipes passing from saidsecond chamber through said third chamber, connections between saidthird chamber. and' said first chamber, and means for forcing air intosaid second,

chamber thence through said pi es into-said first chamber thence throughsai d-first charm-- her into' and through said third chamber,substantially as described.

" HORACE C. GARDNER.

'Witnessesz' MINNIE A. HUNTER,

CHARLES EQBICKARDJA 5. In an apparatus for drying air, the

